Levels of suggestibility are associated with distinct patterns of intrinsic functional neural connectivity

Suggestibility refers to an individual's tendency to accept, believe, and act on information or ideas presented by others with limited critical evaluation or independent judgment. It reflects the extent to which a person's behaviors, choices, thoughts, and memories can be shaped by external prompts, leading questions, or social influences. Despite its relevance to human behaviors, its neuropsychological basis remains poorly understood. In this study, we examined the behavioral, structural, and functional neural correlates of suggestibility in the domains of working memory and attentional control.

We employed the validated Multidimensional Iowa Suggestibility Scale (MISS) to measure the suggestibility of 42 healthy female participants. They were classified into the high suggestibility (HS) (n = 21) and low suggestibility (LS) (n = 21) groups based on their MISS scores. All participants underwent fMRI while performing working memory (N-back) and attentional control (Flanker) tasks, in addition to structural and resting-state scans.

Behaviorally, the HS group exhibited reduced reaction time interference in the Flanker task, suggesting enhanced attentional control. Voxel-based morphometry revealed greater gray matter volume in the right superior frontal gyrus and left postcentral gyrus among HS participants. Task-based activation analyses showed increased activation in frontal, parietal, and temporal regions in the HS group. Resting-state regions of interest (ROI)-to-ROI connectivity analysis revealed a significant increase in connectivity between the salience network (right supramarginal gyrus) and default mode network (right lateral parietal cortex) in the HS group.

Our findings indicate that high and low levels of suggestibility are associated with distinct patterns of intrinsic functional connectivity. Also, suggestibility modulates attentional control, brain structure, and intrinsic functional connectivity. These findings provide important translational insights for applying suggestibility in therapeutic contexts. Future research should continue to elucidate the mechanisms underlying suggestibility and explore how these traits may be leveraged to enhance interventions across diverse populations.